The GetCommMask function retrieves the value of the event mask for a specified communications device.
BOOL GetCommMask(
| HANDLE hFile, | // handle of communications device |
| LPDWORD lpEvtMask | // address of variable to get event mask |
| ); |
Parameters
hFile
Identifies the communications device. The CreateFile function returns this handle.
lpEvtMask
Points to the 32-bit variable to be filled with a mask of events that are currently enabled. This parameter can be one or more of the following values:
| Value | Meaning |
| EV_BREAK | A break was detected on input. |
| EV_CTS | The CTS (clear-to-send) signal changed state. |
| EV_DSR | The DSR (data-set-ready) signal changed state. |
| EV_ERR | A line-status error occurred. Line-status errors are CE_FRAME, CE_OVERRUN, and CE_RXPARITY. |
| EV_EVENT1 | An event of the first provider-specific type occured. |
| EV_EVENT2 | An event of the second provider-specific type occured. |
| EV_PERR | A printer error occured. |
| EV_RING | A ring indicator was detected. |
| EV_RLSD | The RLSD (receive-line-signal-detect) signal changed state. |
| EV_RX80FULL | The receive buffer is 80 percent full. |
| EV_RXCHAR | A character was received and placed in the input buffer. |
| EV_RXFLAG | The event character was received and placed in the input buffer. The event character is specified in the device's DCB structure, which is applied to a serial port by using the SetCommState function. |
| EV_TXEMPTY | The last character in the output buffer was sent. |
Return Values
If the function succeeds, the return value is nonzero.
If the function fails, the return value is zero. To get extended error information, call GetLastError.
Remarks
The GetCommMask function uses a 32-bit mask variable to indicate the set of events that can be monitored for a particular communications resource. A handle to the communications resource can be specified in a call to the WaitCommEvent function, which waits for one of the events to occur. To modify the event mask of a communications resource, use the SetCommMask function.
See Also